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<div class="section">
<div class="titlepage"><div><div>
<h2 class="title">
<a id="modules-node"></a>Node<a class="edit_me edit_me_private" rel="nofollow" title="Editing on GitHub is available to Elastic" href="https://github.com/elastic/elasticsearch/edit/7.7/docs/reference/modules/node.asciidoc">edit</a>
</h2>
</div></div></div>
<p>Any time that you start an instance of Elasticsearch, you are starting a <em>node</em>.
A collection of connected nodes is called a <a class="xref" href="modules-cluster.html" title="Cluster-level shard allocation and routing settings">cluster</a>. If you
are running a single node of Elasticsearch, then you have a cluster of one node.</p>
<p>Every node in the cluster can handle <a class="xref" href="modules-http.html" title="HTTP">HTTP</a> and
<a class="xref" href="modules-transport.html" title="Transport">Transport</a> traffic by default. The transport layer is used
exclusively for communication between nodes; the HTTP layer is used by REST
clients.</p>
<p>All nodes know about all the other nodes in the cluster and can forward client
requests to the appropriate node.</p>
<p>By default, a node is all of the following types: master-eligible, data, ingest,
and (if available) machine learning and transform.</p>
<div class="tip admon">
<div class="icon"></div>
<div class="admon_content">
<p>As the cluster grows and in particular if you have large machine learning jobs or
continuous transforms, consider separating dedicated master-eligible nodes from
dedicated data nodes, machine learning nodes, and transform nodes.</p>
</div>
</div>
<div class="variablelist">
<dl class="variablelist">
<dt>
<span class="term">
<a class="xref" href="modules-node.html#master-node" title="Master-eligible node">Master-eligible node</a>
</span>
</dt>
<dd>
A node that has <code class="literal">node.master</code> set to <code class="literal">true</code> (default), which makes it eligible
to be <a class="xref" href="modules-discovery.html" title="Discovery and cluster formation">elected as the <em>master</em> node</a>, which controls the
cluster.
</dd>
<dt>
<span class="term">
<a class="xref" href="modules-node.html#data-node" title="Data node">Data node</a>
</span>
</dt>
<dd>
A node that has <code class="literal">node.data</code> set to <code class="literal">true</code> (default). Data nodes hold data and
perform data related operations such as CRUD, search, and aggregations.
</dd>
<dt>
<span class="term">
<a class="xref" href="ingest.html" title="Ingest node">Ingest node</a>
</span>
</dt>
<dd>
A node that has <code class="literal">node.ingest</code> set to <code class="literal">true</code> (default). Ingest nodes are able
to apply an <a class="xref" href="pipeline.html" title="Pipeline Definition">ingest pipeline</a> to a document in order to transform
and enrich the document before indexing. With a heavy ingest load, it makes
sense to use dedicated ingest nodes and to mark the master and data nodes as
<code class="literal">node.ingest: false</code>.
</dd>
<dt>
<span class="term">
<a class="xref" href="modules-node.html#ml-node" title="Machine learning node">Machine learning node</a>
</span>
</dt>
<dd>
<p>
A node that has <code class="literal">xpack.ml.enabled</code> and <code class="literal">node.ml</code> set to <code class="literal">true</code>, which is the
default behavior in the Elasticsearch default distribution. If you want to use machine learning features,
there must be at least one machine learning node in your cluster. For more information about
machine learning features, see
<a href="/guide/en/machine-learning/7.7/index.html" class="ulink" target="_top">Machine learning in the Elastic Stack</a>.
</p>
<div class="important admon">
<div class="icon"></div>
<div class="admon_content">
<p>If you use the OSS-only distribution, do not set <code class="literal">node.ml</code>. Otherwise, the node
fails to start.</p>
</div>
</div>
</dd>
<dt>
<span class="term">
<a class="xref" href="modules-node.html#transform-node" title="Transform node">Transform node</a>
</span>
</dt>
<dd>
A node that has <code class="literal">xpack.transform.enabled</code> and <code class="literal">node.transform</code> set to <code class="literal">true</code>. If
you want to use transforms, there must be at least one transform node in
your cluster. For more information, see <a class="xref" href="transform-settings.html" title="Transforms settings in Elasticsearch">Transforms settings</a> and
<a class="xref" href="transforms.html" title="Transforming data"><em>Transforming data</em></a>.
</dd>
</dl>
</div>
<div class="note admon">
<div class="icon"></div>
<div class="admon_content">
<h3>Coordinating node<a id="coordinating-node"></a>
</h3>
<p>Requests like search requests or bulk-indexing requests may involve data held
on different data nodes. A search request, for example, is executed in two
phases which are coordinated by the node which receives the client request — the <em>coordinating node</em>.</p>
<p>In the <em>scatter</em> phase, the coordinating node forwards the request to the data
nodes which hold the data.  Each data node executes the request locally and
returns its results to the coordinating node. In the <em>gather</em>  phase, the
coordinating node reduces each data node’s results into a single global
resultset.</p>
<p>Every node is implicitly a coordinating node. This means that a node that has
all three <code class="literal">node.master</code>, <code class="literal">node.data</code> and <code class="literal">node.ingest</code> set to <code class="literal">false</code> will
only act as a coordinating node, which cannot be disabled. As a result, such
a node needs to have enough memory and CPU in order to deal with the gather
phase.</p>
</div>
</div>
<div class="section">
<div class="titlepage"><div><div>
<h3 class="title">
<a id="master-node"></a>Master-eligible node<a class="edit_me edit_me_private" rel="nofollow" title="Editing on GitHub is available to Elastic" href="https://github.com/elastic/elasticsearch/edit/7.7/docs/reference/modules/node.asciidoc">edit</a>
</h3>
</div></div></div>
<p>The master node is responsible for lightweight cluster-wide actions such as
creating or deleting an index, tracking which nodes are part of the cluster,
and deciding which shards to allocate to which nodes. It is important for
cluster health to have a stable master node.</p>
<p>Any master-eligible node that is not a <a class="xref" href="modules-node.html#voting-only-node" title="Voting-only master-eligible node">voting-only node</a> may
be elected to become the master node by the <a class="xref" href="modules-discovery.html" title="Discovery and cluster formation">master election
process</a>.</p>
<div class="important admon">
<div class="icon"></div>
<div class="admon_content">
<p>Master nodes must have access to the <code class="literal">data/</code> directory (just like
<code class="literal">data</code> nodes) as this is where the cluster state is persisted between node
restarts.</p>
</div>
</div>
<div class="section">
<div class="titlepage"><div><div>
<h4 class="title">
<a id="dedicated-master-node"></a>Dedicated master-eligible node<a class="edit_me edit_me_private" rel="nofollow" title="Editing on GitHub is available to Elastic" href="https://github.com/elastic/elasticsearch/edit/7.7/docs/reference/modules/node.asciidoc">edit</a>
</h4>
</div></div></div>
<p>It is important for the health of the cluster that the elected master node has
the resources it needs to fulfill its responsibilities. If the elected master
node is overloaded with other tasks then the cluster may not operate well. In
particular, indexing and searching your data can be very resource-intensive, so
in large or high-throughput clusters it is a good idea to avoid using the
master-eligible nodes for tasks such as indexing and searching. You can do this
by configuring three of your nodes to be dedicated master-eligible nodes.
Dedicated master-eligible nodes only have the <code class="literal">master</code> role, allowing them to
focus on managing the cluster. While master nodes can also behave as
<a class="xref" href="modules-node.html#coordinating-node" title="Coordinating node">coordinating nodes</a> and route search and indexing requests
from clients to data nodes, it is better <em>not</em> to use dedicated master nodes for
this purpose.</p>
<p>To create a dedicated master-eligible node in the default distribution, set:</p>
<div class="pre_wrapper lang-yaml">
<pre class="programlisting prettyprint lang-yaml">node.master: true <a id="CO12-1"></a><i class="conum" data-value="1"></i>
node.voting_only: false <a id="CO12-2"></a><i class="conum" data-value="2"></i>
node.data: false <a id="CO12-3"></a><i class="conum" data-value="3"></i>
node.ingest: false <a id="CO12-4"></a><i class="conum" data-value="4"></i>
node.ml: false <a id="CO12-5"></a><i class="conum" data-value="5"></i>
xpack.ml.enabled: true <a id="CO12-6"></a><i class="conum" data-value="6"></i>
node.transform: false <a id="CO12-7"></a><i class="conum" data-value="7"></i>
xpack.transform.enabled: true <a id="CO12-8"></a><i class="conum" data-value="8"></i>
node.remote_cluster_client: false <a id="CO12-9"></a><i class="conum" data-value="9"></i></pre>
</div>
<div class="calloutlist">
<table border="0" summary="Callout list">
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO12-1"><i class="conum" data-value="1"></i></a></p>
</td>
<td align="left" valign="top">
<p>The <code class="literal">node.master</code> role is enabled by default.</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO12-2"><i class="conum" data-value="2"></i></a></p>
</td>
<td align="left" valign="top">
<p>The <code class="literal">node.voting_only</code> role is disabled by default.</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO12-3"><i class="conum" data-value="3"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable the <code class="literal">node.data</code> role (enabled by default).</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO12-4"><i class="conum" data-value="4"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable the <code class="literal">node.ingest</code> role (enabled by default).</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO12-5"><i class="conum" data-value="5"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable the <code class="literal">node.ml</code> role (enabled by default).</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO12-6"><i class="conum" data-value="6"></i></a></p>
</td>
<td align="left" valign="top">
<p>The <code class="literal">xpack.ml.enabled</code> setting is enabled by default.</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO12-7"><i class="conum" data-value="7"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable the <code class="literal">node.transform</code> role.</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO12-8"><i class="conum" data-value="8"></i></a></p>
</td>
<td align="left" valign="top">
<p>The <code class="literal">xpack.transform.enabled</code> setting is enabled by default.</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO12-9"><i class="conum" data-value="9"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable remote cluster connections (enabled by default).</p>
</td>
</tr>
</table>
</div>
<p>To create a dedicated master-eligible node in the OSS-only distribution, set:</p>
<div class="pre_wrapper lang-yaml">
<pre class="programlisting prettyprint lang-yaml">node.master: true <a id="CO13-1"></a><i class="conum" data-value="1"></i>
node.data: false <a id="CO13-2"></a><i class="conum" data-value="2"></i>
node.ingest: false <a id="CO13-3"></a><i class="conum" data-value="3"></i>
node.remote_cluster_client: false <a id="CO13-4"></a><i class="conum" data-value="4"></i></pre>
</div>
<div class="calloutlist">
<table border="0" summary="Callout list">
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO13-1"><i class="conum" data-value="1"></i></a></p>
</td>
<td align="left" valign="top">
<p>The <code class="literal">node.master</code> role is enabled by default.</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO13-2"><i class="conum" data-value="2"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable the <code class="literal">node.data</code> role (enabled by default).</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO13-3"><i class="conum" data-value="3"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable the <code class="literal">node.ingest</code> role (enabled by default).</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO13-4"><i class="conum" data-value="4"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable remote cluster connections (enabled by default).</p>
</td>
</tr>
</table>
</div>
</div>

<div class="section">
<div class="titlepage"><div><div>
<h4 class="title">
<a id="voting-only-node"></a>Voting-only master-eligible node<a class="edit_me edit_me_private" rel="nofollow" title="Editing on GitHub is available to Elastic" href="https://github.com/elastic/elasticsearch/edit/7.7/docs/reference/modules/node.asciidoc">edit</a>
</h4>
</div></div></div>
<p>A voting-only master-eligible node is a node that participates in
<a class="xref" href="modules-discovery.html" title="Discovery and cluster formation">master elections</a> but which will not act as the cluster’s
elected master node. In particular, a voting-only node can serve as a tiebreaker
in elections.</p>
<p>It may seem confusing to use the term "master-eligible" to describe a
voting-only node since such a node is not actually eligible to become the master
at all. This terminology is an unfortunate consequence of history:
master-eligible nodes are those nodes that participate in elections and perform
certain tasks during cluster state publications, and voting-only nodes have the
same responsibilities even if they can never become the elected master.</p>
<p>To configure a master-eligible node as a voting-only node, set the following
setting:</p>
<div class="pre_wrapper lang-yaml">
<pre class="programlisting prettyprint lang-yaml">node.voting_only: true <a id="CO14-1"></a><i class="conum" data-value="1"></i></pre>
</div>
<div class="calloutlist">
<table border="0" summary="Callout list">
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO14-1"><i class="conum" data-value="1"></i></a></p>
</td>
<td align="left" valign="top">
<p>The default for <code class="literal">node.voting_only</code> is <code class="literal">false</code>.</p>
</td>
</tr>
</table>
</div>
<div class="important admon">
<div class="icon"></div>
<div class="admon_content">
<p>The <code class="literal">voting_only</code> role requires the default distribution of Elasticsearch and is not
supported in the OSS-only distribution. If you use the OSS-only distribution and set
<code class="literal">node.voting_only</code> then the node will fail to start.  Also note that only
master-eligible nodes can be marked as voting-only.</p>
</div>
</div>
<p>High availability (HA) clusters require at least three master-eligible nodes, at
least two of which are not voting-only nodes. Such a cluster will be able to
elect a master node even if one of the nodes fails.</p>
<p>Since voting-only nodes never act as the cluster’s elected master, they may
require require less heap and a less powerful CPU than the true master nodes.
However all master-eligible nodes, including voting-only nodes, require
reasonably fast persistent storage and a reliable and low-latency network
connection to the rest of the cluster, since they are on the critical path for
<a class="xref" href="cluster-state-publishing.html" title="Publishing the cluster state">publishing cluster state updates</a>.</p>
<p>Voting-only master-eligible nodes may also fill other roles in your cluster.
For instance, a node may be both a data node and a voting-only master-eligible
node. A <em>dedicated</em> voting-only master-eligible nodes is a voting-only
master-eligible node that fills no other roles in the cluster. To create a
dedicated voting-only master-eligible node in the default distribution, set:</p>
<div class="pre_wrapper lang-yaml">
<pre class="programlisting prettyprint lang-yaml">node.master: true <a id="CO15-1"></a><i class="conum" data-value="1"></i>
node.voting_only: true <a id="CO15-2"></a><i class="conum" data-value="2"></i>
node.data: false <a id="CO15-3"></a><i class="conum" data-value="3"></i>
node.ingest: false <a id="CO15-4"></a><i class="conum" data-value="4"></i>
node.ml: false <a id="CO15-5"></a><i class="conum" data-value="5"></i>
xpack.ml.enabled: true <a id="CO15-6"></a><i class="conum" data-value="6"></i>
node.transform: false <a id="CO15-7"></a><i class="conum" data-value="7"></i>
xpack.transform.enabled: true <a id="CO15-8"></a><i class="conum" data-value="8"></i>
node.remote_cluster_client: false <a id="CO15-9"></a><i class="conum" data-value="9"></i></pre>
</div>
<div class="calloutlist">
<table border="0" summary="Callout list">
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO15-1"><i class="conum" data-value="1"></i></a></p>
</td>
<td align="left" valign="top">
<p>The <code class="literal">node.master</code> role is enabled by default.</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO15-2"><i class="conum" data-value="2"></i></a></p>
</td>
<td align="left" valign="top">
<p>Enable the <code class="literal">node.voting_only</code> role (disabled by default).</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO15-3"><i class="conum" data-value="3"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable the <code class="literal">node.data</code> role (enabled by default).</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO15-4"><i class="conum" data-value="4"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable the <code class="literal">node.ingest</code> role (enabled by default).</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO15-5"><i class="conum" data-value="5"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable the <code class="literal">node.ml</code> role (enabled by default).</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO15-6"><i class="conum" data-value="6"></i></a></p>
</td>
<td align="left" valign="top">
<p>The <code class="literal">xpack.ml.enabled</code> setting is enabled by default.</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO15-7"><i class="conum" data-value="7"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable the <code class="literal">node.transform</code> role.</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO15-8"><i class="conum" data-value="8"></i></a></p>
</td>
<td align="left" valign="top">
<p>The <code class="literal">xpack.transform.enabled</code> setting is enabled by default.</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO15-9"><i class="conum" data-value="9"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable remote cluster connections (enabled by default).</p>
</td>
</tr>
</table>
</div>
</div>

</div>

<div class="section">
<div class="titlepage"><div><div>
<h3 class="title">
<a id="data-node"></a>Data node<a class="edit_me edit_me_private" rel="nofollow" title="Editing on GitHub is available to Elastic" href="https://github.com/elastic/elasticsearch/edit/7.7/docs/reference/modules/node.asciidoc">edit</a>
</h3>
</div></div></div>
<p>Data nodes hold the shards that contain the documents you have indexed. Data
nodes handle data related operations like CRUD, search, and aggregations.
These operations are I/O-, memory-, and CPU-intensive. It is important to
monitor these resources and to add more data nodes if they are overloaded.</p>
<p>The main benefit of having dedicated data nodes is the separation of the master
and data roles.</p>
<p>To create a dedicated data node in the default distribution, set:</p>
<div class="pre_wrapper lang-yaml">
<pre class="programlisting prettyprint lang-yaml">node.master: false <a id="CO16-1"></a><i class="conum" data-value="1"></i>
node.voting_only: false <a id="CO16-2"></a><i class="conum" data-value="2"></i>
node.data: true <a id="CO16-3"></a><i class="conum" data-value="3"></i>
node.ingest: false <a id="CO16-4"></a><i class="conum" data-value="4"></i>
node.ml: false <a id="CO16-5"></a><i class="conum" data-value="5"></i>
node.transform: false <a id="CO16-6"></a><i class="conum" data-value="6"></i>
xpack.transform.enabled: true <a id="CO16-7"></a><i class="conum" data-value="7"></i>
node.remote_cluster_client: false <a id="CO16-8"></a><i class="conum" data-value="8"></i></pre>
</div>
<div class="calloutlist">
<table border="0" summary="Callout list">
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO16-1"><i class="conum" data-value="1"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable the <code class="literal">node.master</code> role (enabled by default).</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO16-2"><i class="conum" data-value="2"></i></a></p>
</td>
<td align="left" valign="top">
<p>The <code class="literal">node.voting_only</code> role is disabled by default.</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO16-3"><i class="conum" data-value="3"></i></a></p>
</td>
<td align="left" valign="top">
<p>The <code class="literal">node.data</code> role is enabled by default.</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO16-4"><i class="conum" data-value="4"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable the <code class="literal">node.ingest</code> role (enabled by default).</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO16-5"><i class="conum" data-value="5"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable the <code class="literal">node.ml</code> role (enabled by default).</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO16-6"><i class="conum" data-value="6"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable the <code class="literal">node.transform</code> role.</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO16-7"><i class="conum" data-value="7"></i></a></p>
</td>
<td align="left" valign="top">
<p>The <code class="literal">xpack.transform.enabled</code> setting is enabled by default.</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO16-8"><i class="conum" data-value="8"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable remote cluster connections (enabled by default).</p>
</td>
</tr>
</table>
</div>
<p>To create a dedicated data node in the OSS-only distribution, set:</p>
<div class="pre_wrapper lang-yaml">
<pre class="programlisting prettyprint lang-yaml">node.master: false <a id="CO17-1"></a><i class="conum" data-value="1"></i>
node.data: true <a id="CO17-2"></a><i class="conum" data-value="2"></i>
node.ingest: false <a id="CO17-3"></a><i class="conum" data-value="3"></i>
node.remote_cluster_client: false <a id="CO17-4"></a><i class="conum" data-value="4"></i></pre>
</div>
<div class="calloutlist">
<table border="0" summary="Callout list">
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO17-1"><i class="conum" data-value="1"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable the <code class="literal">node.master</code> role (enabled by default).</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO17-2"><i class="conum" data-value="2"></i></a></p>
</td>
<td align="left" valign="top">
<p>The <code class="literal">node.data</code> role is enabled by default.</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO17-3"><i class="conum" data-value="3"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable the <code class="literal">node.ingest</code> role (enabled by default).</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO17-4"><i class="conum" data-value="4"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable remote cluster connections (enabled by default).</p>
</td>
</tr>
</table>
</div>
</div>

<div class="section">
<div class="titlepage"><div><div>
<h3 class="title">
<a id="node-ingest-node"></a>Ingest node<a class="edit_me edit_me_private" rel="nofollow" title="Editing on GitHub is available to Elastic" href="https://github.com/elastic/elasticsearch/edit/7.7/docs/reference/modules/node.asciidoc">edit</a>
</h3>
</div></div></div>
<p>Ingest nodes can execute pre-processing pipelines, composed of one or more
ingest processors. Depending on the type of operations performed by the ingest
processors and the required resources, it may make sense to have dedicated
ingest nodes, that will only perform this specific task.</p>
<p>To create a dedicated ingest node in the default distribution, set:</p>
<div class="pre_wrapper lang-yaml">
<pre class="programlisting prettyprint lang-yaml">node.master: false <a id="CO18-1"></a><i class="conum" data-value="1"></i>
node.voting_only: false <a id="CO18-2"></a><i class="conum" data-value="2"></i>
node.data: false <a id="CO18-3"></a><i class="conum" data-value="3"></i>
node.ingest: true <a id="CO18-4"></a><i class="conum" data-value="4"></i>
node.ml: false <a id="CO18-5"></a><i class="conum" data-value="5"></i>
node.transform: false <a id="CO18-6"></a><i class="conum" data-value="6"></i>
node.remote_cluster_client: false <a id="CO18-7"></a><i class="conum" data-value="7"></i></pre>
</div>
<div class="calloutlist">
<table border="0" summary="Callout list">
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO18-1"><i class="conum" data-value="1"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable the <code class="literal">node.master</code> role (enabled by default).</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO18-2"><i class="conum" data-value="2"></i></a></p>
</td>
<td align="left" valign="top">
<p>The <code class="literal">node.voting_only</code> role is disabled by default.</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO18-3"><i class="conum" data-value="3"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable the <code class="literal">node.data</code> role (enabled by default).</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO18-4"><i class="conum" data-value="4"></i></a></p>
</td>
<td align="left" valign="top">
<p>The <code class="literal">node.ingest</code> role is enabled by default.</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO18-5"><i class="conum" data-value="5"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable the <code class="literal">node.ml</code> role (enabled by default).</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO18-6"><i class="conum" data-value="6"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable the <code class="literal">node.transform</code> role.</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO18-7"><i class="conum" data-value="7"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable remote cluster connections (enabled by default).</p>
</td>
</tr>
</table>
</div>
<p>To create a dedicated ingest node in the OSS-only distribution, set:</p>
<div class="pre_wrapper lang-yaml">
<pre class="programlisting prettyprint lang-yaml">node.master: false <a id="CO19-1"></a><i class="conum" data-value="1"></i>
node.data: false <a id="CO19-2"></a><i class="conum" data-value="2"></i>
node.ingest: true <a id="CO19-3"></a><i class="conum" data-value="3"></i>
node.remote_cluster_client: false <a id="CO19-4"></a><i class="conum" data-value="4"></i></pre>
</div>
<div class="calloutlist">
<table border="0" summary="Callout list">
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO19-1"><i class="conum" data-value="1"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable the <code class="literal">node.master</code> role (enabled by default).</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO19-2"><i class="conum" data-value="2"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable the <code class="literal">node.data</code> role (enabled by default).</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO19-3"><i class="conum" data-value="3"></i></a></p>
</td>
<td align="left" valign="top">
<p>The <code class="literal">node.ingest</code> role is enabled by default.</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO19-4"><i class="conum" data-value="4"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable remote cluster connections (enabled by default).</p>
</td>
</tr>
</table>
</div>
</div>

<div class="section">
<div class="titlepage"><div><div>
<h3 class="title">
<a id="coordinating-only-node"></a>Coordinating only node<a class="edit_me edit_me_private" rel="nofollow" title="Editing on GitHub is available to Elastic" href="https://github.com/elastic/elasticsearch/edit/7.7/docs/reference/modules/node.asciidoc">edit</a>
</h3>
</div></div></div>
<p>If you take away the ability to be able to handle master duties, to hold data,
and pre-process documents, then you are left with a <em>coordinating</em> node that
can only route requests, handle the search reduce phase, and distribute bulk
indexing. Essentially, coordinating only nodes behave as smart load balancers.</p>
<p>Coordinating only nodes can benefit large clusters by offloading the
coordinating node role from data and master-eligible nodes.  They join the
cluster and receive the full <a class="xref" href="cluster-state.html" title="Cluster state API">cluster state</a>, like every other
node, and they use the cluster state to route requests directly to the
appropriate place(s).</p>
<div class="warning admon">
<div class="icon"></div>
<div class="admon_content">
<p>Adding too many coordinating only nodes to a cluster can increase the
burden on the entire cluster because the elected master node must await
acknowledgement of cluster state updates from every node! The benefit of
coordinating only nodes should not be overstated — data nodes can happily
serve the same purpose.</p>
</div>
</div>
<p>To create a dedicated coordinating node in the default distribution, set:</p>
<div class="pre_wrapper lang-yaml">
<pre class="programlisting prettyprint lang-yaml">node.master: false <a id="CO20-1"></a><i class="conum" data-value="1"></i>
node.voting_only: false <a id="CO20-2"></a><i class="conum" data-value="2"></i>
node.data: false <a id="CO20-3"></a><i class="conum" data-value="3"></i>
node.ingest: false <a id="CO20-4"></a><i class="conum" data-value="4"></i>
node.ml: false <a id="CO20-5"></a><i class="conum" data-value="5"></i>
xpack.ml.enabled: true <a id="CO20-6"></a><i class="conum" data-value="6"></i>
node.transform: false <a id="CO20-7"></a><i class="conum" data-value="7"></i>
xpack.transform.enabled: true <a id="CO20-8"></a><i class="conum" data-value="8"></i>
node.remote_cluster_client: false <a id="CO20-9"></a><i class="conum" data-value="9"></i></pre>
</div>
<div class="calloutlist">
<table border="0" summary="Callout list">
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO20-1"><i class="conum" data-value="1"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable the <code class="literal">node.master</code> role (enabled by default).</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO20-2"><i class="conum" data-value="2"></i></a></p>
</td>
<td align="left" valign="top">
<p>The <code class="literal">node.voting_only</code> role is disabled by default.</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO20-3"><i class="conum" data-value="3"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable the <code class="literal">node.data</code> role (enabled by default).</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO20-4"><i class="conum" data-value="4"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable the <code class="literal">node.ingest</code> role (enabled by default).</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO20-5"><i class="conum" data-value="5"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable the <code class="literal">node.ml</code> role (enabled by default).</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO20-6"><i class="conum" data-value="6"></i></a></p>
</td>
<td align="left" valign="top">
<p>The <code class="literal">xpack.ml.enabled</code> setting is enabled by default.</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO20-7"><i class="conum" data-value="7"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable the <code class="literal">node.transform</code> role.</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO20-8"><i class="conum" data-value="8"></i></a></p>
</td>
<td align="left" valign="top">
<p>The <code class="literal">xpack.transform.enabled</code> setting is enabled by default.</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO20-9"><i class="conum" data-value="9"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable remote cluster connections (enabled by default).</p>
</td>
</tr>
</table>
</div>
<p>To create a dedicated coordinating node in the OSS-only distribution, set:</p>
<div class="pre_wrapper lang-yaml">
<pre class="programlisting prettyprint lang-yaml">node.master: false <a id="CO21-1"></a><i class="conum" data-value="1"></i>
node.data: false <a id="CO21-2"></a><i class="conum" data-value="2"></i>
node.ingest: false <a id="CO21-3"></a><i class="conum" data-value="3"></i>
node.remote_cluster_client: false <a id="CO21-4"></a><i class="conum" data-value="4"></i></pre>
</div>
<div class="calloutlist">
<table border="0" summary="Callout list">
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO21-1"><i class="conum" data-value="1"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable the <code class="literal">node.master</code> role (enabled by default).</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO21-2"><i class="conum" data-value="2"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable the <code class="literal">node.data</code> role (enabled by default).</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO21-3"><i class="conum" data-value="3"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable the <code class="literal">node.ingest</code> role (enabled by default).</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO21-4"><i class="conum" data-value="4"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable remote cluster connections (enabled by default).</p>
</td>
</tr>
</table>
</div>
</div>

<div class="section">
<div class="titlepage"><div><div>
<h3 class="title">
<a id="ml-node"></a><span class="xpack">Machine learning node</span><a class="xpack_tag" href="/subscriptions"></a><a class="edit_me edit_me_private" rel="nofollow" title="Editing on GitHub is available to Elastic" href="https://github.com/elastic/elasticsearch/edit/7.7/docs/reference/modules/node.asciidoc">edit</a>
</h3>
</div></div></div>
<p>The machine learning features provide machine learning nodes, which run jobs and handle machine learning API
requests. If <code class="literal">xpack.ml.enabled</code> is set to <code class="literal">true</code> and <code class="literal">node.ml</code> is set to <code class="literal">false</code>,
the node can service API requests but it cannot run jobs.</p>
<p>If you want to use machine learning features in your cluster, you must enable machine learning
(set <code class="literal">xpack.ml.enabled</code> to <code class="literal">true</code>) on all master-eligible nodes. If you want to
use machine learning features in clients (including Kibana), it must also be enabled on all
coordinating nodes. If you have the OSS-only distribution, do not use these settings.</p>
<p>For more information about these settings, see <a class="xref" href="ml-settings.html" title="Machine learning settings in Elasticsearch">Machine learning settings</a>.</p>
<p>To create a dedicated machine learning node in the default distribution, set:</p>
<div class="pre_wrapper lang-yaml">
<pre class="programlisting prettyprint lang-yaml">node.master: false <a id="CO22-1"></a><i class="conum" data-value="1"></i>
node.voting_only: false <a id="CO22-2"></a><i class="conum" data-value="2"></i>
node.data: false <a id="CO22-3"></a><i class="conum" data-value="3"></i>
node.ingest: false <a id="CO22-4"></a><i class="conum" data-value="4"></i>
node.ml: true <a id="CO22-5"></a><i class="conum" data-value="5"></i>
xpack.ml.enabled: true <a id="CO22-6"></a><i class="conum" data-value="6"></i>
node.transform: false <a id="CO22-7"></a><i class="conum" data-value="7"></i>
xpack.transform.enabled: true <a id="CO22-8"></a><i class="conum" data-value="8"></i>
node.remote_cluster_client: false <a id="CO22-9"></a><i class="conum" data-value="9"></i></pre>
</div>
<div class="calloutlist">
<table border="0" summary="Callout list">
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO22-1"><i class="conum" data-value="1"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable the <code class="literal">node.master</code> role (enabled by default).</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO22-2"><i class="conum" data-value="2"></i></a></p>
</td>
<td align="left" valign="top">
<p>The <code class="literal">node.voting_only</code> role is disabled by default.</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO22-3"><i class="conum" data-value="3"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable the <code class="literal">node.data</code> role (enabled by default).</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO22-4"><i class="conum" data-value="4"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable the <code class="literal">node.ingest</code> role (enabled by default).</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO22-5"><i class="conum" data-value="5"></i></a></p>
</td>
<td align="left" valign="top">
<p>The <code class="literal">node.ml</code> role is enabled by default.</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO22-6"><i class="conum" data-value="6"></i></a></p>
</td>
<td align="left" valign="top">
<p>The <code class="literal">xpack.ml.enabled</code> setting is enabled by default.</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO22-7"><i class="conum" data-value="7"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable the <code class="literal">node.transform</code> role.</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO22-8"><i class="conum" data-value="8"></i></a></p>
</td>
<td align="left" valign="top">
<p>The <code class="literal">xpack.transform.enabled</code> setting is enabled by default.</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO22-9"><i class="conum" data-value="9"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable remote cluster connections (enabled by default).</p>
</td>
</tr>
</table>
</div>
</div>

<div class="section">
<div class="titlepage"><div><div>
<h3 class="title">
<a id="transform-node"></a><span class="xpack">Transform node</span><a class="xpack_tag" href="/subscriptions"></a><a class="edit_me edit_me_private" rel="nofollow" title="Editing on GitHub is available to Elastic" href="https://github.com/elastic/elasticsearch/edit/7.7/docs/reference/modules/node.asciidoc">edit</a>
</h3>
</div></div></div>
<p>Transform nodes run transforms and handle transform API requests.</p>
<p>If you want to use transforms in your cluster, you must have
<code class="literal">xpack.transform.enabled</code> set to <code class="literal">true</code> on all master-eligible nodes and all
data nodes. If you want to use transforms in clients (including Kibana), it
must also be enabled on all coordinating nodes. You must also have
<code class="literal">node.transform</code> set to <code class="literal">true</code> on at least one node. This is the default
behavior. If you have the OSS-only distribution, do not use these settings. For more
information, see <a class="xref" href="transform-settings.html" title="Transforms settings in Elasticsearch">Transforms settings</a>.</p>
<p>To create a dedicated transform node in the default distribution, set:</p>
<div class="pre_wrapper lang-yaml">
<pre class="programlisting prettyprint lang-yaml">node.master: false <a id="CO23-1"></a><i class="conum" data-value="1"></i>
node.voting_only: false <a id="CO23-2"></a><i class="conum" data-value="2"></i>
node.data: false <a id="CO23-3"></a><i class="conum" data-value="3"></i>
node.ingest: false <a id="CO23-4"></a><i class="conum" data-value="4"></i>
node.ml: false <a id="CO23-5"></a><i class="conum" data-value="5"></i>
node.transform: true <a id="CO23-6"></a><i class="conum" data-value="6"></i>
xpack.transform.enabled: true <a id="CO23-7"></a><i class="conum" data-value="7"></i>
node.remote_cluster_client: false <a id="CO23-8"></a><i class="conum" data-value="8"></i></pre>
</div>
<div class="calloutlist">
<table border="0" summary="Callout list">
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO23-1"><i class="conum" data-value="1"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable the <code class="literal">node.master</code> role.</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO23-2"><i class="conum" data-value="2"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable the <code class="literal">node.voting_only</code>.</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO23-3"><i class="conum" data-value="3"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable the <code class="literal">node.data</code> role.</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO23-4"><i class="conum" data-value="4"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable the <code class="literal">node.ingest</code> role.</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO23-5"><i class="conum" data-value="5"></i></a></p>
</td>
<td align="left" valign="top">
<p>Enable the <code class="literal">node.ml</code> role.</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO23-6"><i class="conum" data-value="6"></i></a></p>
</td>
<td align="left" valign="top">
<p>Enable the <code class="literal">node.transform</code> role.</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO23-7"><i class="conum" data-value="7"></i></a></p>
</td>
<td align="left" valign="top">
<p>Enable the <code class="literal">xpack.transform.enabled</code> setting.</p>
</td>
</tr>
<tr>
<td align="left" valign="top" width="5%">
<p><a href="#CO23-8"><i class="conum" data-value="8"></i></a></p>
</td>
<td align="left" valign="top">
<p>Disable remote cluster connections.</p>
</td>
</tr>
</table>
</div>
</div>

<div class="section">
<div class="titlepage"><div><div>
<h3 class="title">
<a id="change-node-role"></a>Changing the role of a node<a class="edit_me edit_me_private" rel="nofollow" title="Editing on GitHub is available to Elastic" href="https://github.com/elastic/elasticsearch/edit/7.7/docs/reference/modules/node.asciidoc">edit</a>
</h3>
</div></div></div>
<p>Each data node maintains the following data on disk:</p>
<div class="ulist itemizedlist">
<ul class="itemizedlist">
<li class="listitem">
the shard data for every shard allocated to that node,
</li>
<li class="listitem">
the index metadata corresponding with every shard allocated to that node, and
</li>
<li class="listitem">
the cluster-wide metadata, such as settings and index templates.
</li>
</ul>
</div>
<p>Similarly, each master-eligible node maintains the following data on disk:</p>
<div class="ulist itemizedlist">
<ul class="itemizedlist">
<li class="listitem">
the index metadata for every index in the cluster, and
</li>
<li class="listitem">
the cluster-wide metadata, such as settings and index templates.
</li>
</ul>
</div>
<p>Each node checks the contents of its data path at startup. If it discovers
unexpected data then it will refuse to start. This is to avoid importing
unwanted <a class="xref" href="modules-gateway-dangling-indices.html" title="Dangling indices">dangling indices</a> which can lead
to a red cluster health. To be more precise, nodes with <code class="literal">node.data: false</code> will
refuse to start if they find any shard data on disk at startup, and nodes with
both <code class="literal">node.master: false</code> and <code class="literal">node.data: false</code> will refuse to start if they
have any index metadata on disk at startup.</p>
<p>It is possible to change the roles of a node by adjusting its
<code class="literal">elasticsearch.yml</code> file and restarting it. This is known as <em>repurposing</em> a
node. In order to satisfy the checks for unexpected data described above, you
must perform some extra steps to prepare a node for repurposing when setting
its <code class="literal">node.data</code> or <code class="literal">node.master</code> roles to <code class="literal">false</code>:</p>
<div class="ulist itemizedlist">
<ul class="itemizedlist">
<li class="listitem">
If you want to repurpose a data node by changing <code class="literal">node.data</code> to <code class="literal">false</code> then
you should first use an <a class="xref" href="allocation-filtering.html" title="Cluster-level shard allocation filtering">allocation filter</a> to safely
migrate all the shard data onto other nodes in the cluster.
</li>
<li class="listitem">
If you want to repurpose a node to have both <code class="literal">node.master: false</code> and
<code class="literal">node.data: false</code> then it is simplest to start a brand-new node with an
empty data path and the desired roles. You may find it safest to use an
<a class="xref" href="allocation-filtering.html" title="Cluster-level shard allocation filtering">allocation filter</a> to migrate the shard data
elsewhere in the cluster first.
</li>
</ul>
</div>
<p>If it is not possible to follow these extra steps then you may be able to use
the <a class="xref" href="node-tool.html#node-tool-repurpose" title="Changing the role of a node"><code class="literal">elasticsearch-node repurpose</code></a> tool to delete any
excess data that prevents a node from starting.</p>
<h3>
<a id="_node_data_path_settings"></a>Node data path settings<a class="edit_me edit_me_private" rel="nofollow" title="Editing on GitHub is available to Elastic" href="https://github.com/elastic/elasticsearch/edit/7.7/docs/reference/modules/node.asciidoc">edit</a>
</h3>
</div>

<div class="section">
<div class="titlepage"><div><div>
<h3 class="title">
<a id="data-path"></a><code class="literal">path.data</code><a class="edit_me edit_me_private" rel="nofollow" title="Editing on GitHub is available to Elastic" href="https://github.com/elastic/elasticsearch/edit/7.7/docs/reference/modules/node.asciidoc">edit</a>
</h3>
</div></div></div>
<p>Every data and master-eligible node requires access to a data directory where
shards and index and cluster metadata will be stored. The <code class="literal">path.data</code> defaults
to <code class="literal">$ES_HOME/data</code> but can be configured in the <code class="literal">elasticsearch.yml</code> config
file an absolute path or a path relative to <code class="literal">$ES_HOME</code> as follows:</p>
<div class="pre_wrapper lang-yaml">
<pre class="programlisting prettyprint lang-yaml">path.data:  /var/elasticsearch/data</pre>
</div>
<p>Like all node settings, it can also be specified on the command line as:</p>
<div class="pre_wrapper lang-sh">
<pre class="programlisting prettyprint lang-sh">./bin/elasticsearch -Epath.data=/var/elasticsearch/data</pre>
</div>
<div class="tip admon">
<div class="icon"></div>
<div class="admon_content">
<p>When using the <code class="literal">.zip</code> or <code class="literal">.tar.gz</code> distributions, the <code class="literal">path.data</code> setting
should be configured to locate the data directory outside the Elasticsearch home
directory, so that the home directory can be deleted without deleting your data!
The RPM and Debian distributions do this for you already.</p>
</div>
</div>
<h3>
<a id="max-local-storage-nodes"></a><code class="literal">node.max_local_storage_nodes</code><a class="edit_me edit_me_private" rel="nofollow" title="Editing on GitHub is available to Elastic" href="https://github.com/elastic/elasticsearch/edit/7.7/docs/reference/modules/node.asciidoc">edit</a>
</h3>
<p>The <a class="xref" href="modules-node.html#data-path" title="path.data">data path</a> can be shared by multiple nodes, even by nodes from
different clusters. It is recommended however to only run one node of Elasticsearch using
the same data path. This setting is deprecated in 7.x and will be removed in
version 8.0.</p>
<p>By default, Elasticsearch is configured to prevent more than one node from sharing the
same data path. To allow for more than one node (e.g., on your development
machine), use the setting <code class="literal">node.max_local_storage_nodes</code> and set this to a
positive integer larger than one.</p>
<div class="warning admon">
<div class="icon"></div>
<div class="admon_content">
<p>Never run different node types (i.e. master, data) from the same data
directory. This can lead to unexpected data loss.</p>
</div>
</div>
<h3>
<a id="other-node-settings"></a>Other node settings<a class="edit_me edit_me_private" rel="nofollow" title="Editing on GitHub is available to Elastic" href="https://github.com/elastic/elasticsearch/edit/7.7/docs/reference/modules/node.asciidoc">edit</a>
</h3>
<p>More node settings can be found in <a class="xref" href="settings.html" title="Configuring Elasticsearch"><em>Configuring Elasticsearch</em></a> and <a class="xref" href="important-settings.html" title="Important Elasticsearch configuration"><em>Important Elasticsearch configuration</em></a>,
including:</p>
<div class="ulist itemizedlist">
<ul class="itemizedlist">
<li class="listitem">
<a class="xref" href="cluster.name.html" title="cluster.name"><code class="literal">cluster.name</code></a>
</li>
<li class="listitem">
<a class="xref" href="node.name.html" title="node.name"><code class="literal">node.name</code></a>
</li>
<li class="listitem">
<a class="xref" href="modules-network.html" title="Network settings">network settings</a>
</li>
</ul>
</div>
</div>

</div>
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